For those who may not understand the comparisons with Fukushima, there were two things that happened there that matter. Fukushima had 4 reactors. 1, 2, and 3 all had meltdowns and the spent fuel storage for those reactors also lost cooling which eventually led to the hydrogen explosions and fires as the spent fuel overheated, boiled off the cooling water remaining after pumps quit working, melted, caught fire, and burned liberating radioactive elements. Luckily, prevailing winds were offshore or the radioactive fallout from Fukushima would have had much more impact on the area. #4 was shut down for maintenance and so even with the outages, it didn’t melt down and it’s fuel rods in storage had already decayed out a lot of the short half life stuff that contributes so much heat. Those rods came close but never boiled away all their water.
The earthquake and tsunami caused the reactors and cooling ponds to lose cooling. The thing about nuclear fuel is all the desired nuclear reactions and split atoms form new elements, generally also radioactive, but usually with much shorter half lives. Short half lives mean lots of spontaneous fissions that generate heat and form new elements. The way it works is it all decays to lead eventually with whatever other lighter elements created in the fissioning. But these decay products are created in the fuel rods and are trapped there. As reactors run and these decay products build in, the fuel rods heat themselves and it gets unsafe to run them for longer time because that heat just is. You can’t control it with control rods. It happens no matter what and is just a consequence and byproduct of burning the main fuel. In normal operation, once the rods decay off enough of the short half life stuff, the remaining unreacted uranium gets separated and made into new fuel.
What’s happening now is Russia is playing Russian roulette with the Zaporizhzhia nuclear power plant fuel storage. Reports are now that Russia wants blackouts to put more pressure on Ukraine as Russia loses the war. Not sure how many of their reactors are still running but if the plant shuts down or loses power apparently over a single transmission line now, the spent fuel rod cooling ponds will lose their pumps and supply of water and start heating, boiling, and eventually the rods get so hot that remaining water gets split thermally into O2 and H2 in the perfect ratio to recombine explosively - as happened in Fukushima. That will open any shelters over the spent fuel and allow fires to spread the radiation to the prevailing wind. (https://www.bbc.com/news/live/62462223) The reactors are also a danger for the same reason. You can SCRAM them but they need cooling or else they heat and melt there too.
It all makes me wonder what part of prevailing winds and nuclear fallout Erdogan (Turkey’s prez and Putin’s close buddy) doesn’t understand. This time of year the prevailing winds would carry fallout from Zaporizhzhia the hop, skip, and a jump straight to Istanbul. Windy shows prevailing winds as they are now and it’s a straight line. (https://www.windy.com/?43.421,31.904,6) If Zaporizhzhia loses cooling and those ponds go up, the fallout goes right to western Turkey and eastern Bulgaria.
There’s some interesting shows on HBO that can provide more insight. The most explanatory is the miniseries Chernobyl. It’s a dramatization that tried and did amazingly well to stay true to the facts but the entire series graphically shows the realities of nuclear fallout. Even if Zaporizhzhia doesn’t have reactor meltdowns, the amount of fuel in cooling ponds could be huge (no idea how much is there but with six reactors, probably a lot) and possibly much more of a threat than the reactors themselves. The other show is called The Chernobyl Tapes and are the film and video logs the Russians made of the Chernobyl disaster. Quality is hit and miss but the point is clear - Chernobyl was a literal hell on earth. Some film is extremely degraded because of radiation flashes that “exposed” it. But they show graphically what happens to people exposed to radiation and contamination. They also showed the deformed animals and babies that were born after Chernobyl blew - just a single reactor. It’s horrific. Radiation and fallout can also render many areas uninhabitable for hundreds of years just as with areas around Chernobyl that the Russian soldiers dug into last March and soon started suffering massive radiation sickness - 36 years after the disaster.
This is what Putin risks with his flailing war in Ukraine and he doesn’t seem to mind. The Zaporihzhzia nuclear plant is the biggest in Europe. There’s likely lots of fuel there. And once it overheats and starts burning, there’s not a lot that can be done but try to douse it with drops of boron and sand like Russia tried with Chernobyl (which later was determined to be hardly effective). The massive radiation levels kill robots. Russia ended up using humans - biorobots - (aka liquidators) since they could work in high radiation to clear debris and contamination even though it meant many would die soon after. Russia recruited some 600,000 liquidators and 100,000 were expected to die. Many are disabled. Their lives were ruined. https://en.wikipedia.org/wiki/Chernobyl_liquidators
It’s a fucking nightmare scenario. It’s not dropping nuclear bombs but it could have similar or greater effects in the long run. War has long been considered a risk to nuclear power plants but the risks were probably minimized and neglected. nobody would deliberately target a power plant, would they? Now we have it front and center and if that plant loses power and the fuel rods light off, eastern Europe is fucked and where gets fucked all depends on the prevailing winds.
Anyway, just more fun stressful needless crap being perpetrated by another fascist madman who was allowed power he had no business being trusted with. Hey Russian generals - Putin needs to die.
Current status of Ukraine’s nuclear plants (as of a week ago) had two reactors still running and just one set of powerlines to get energy out but also to provide power back in to keep spent fuel and reactors cool in the event all get shut down: https://www.oecd-nea.org/jcms/pl_66130/ukraine-current-status-of-nuclear-power-installations
Update - the BBC link I cited now has an expert saying the risk to the reactors is low.
”An expert from Imperial College, London, has been giving some reassurance about the danger of a nuclear accident at the nuclear power plant in Zaporizhzhia. Dr Mark Wenman says it is "a relatively modern and robust reactor design," unlike the reactor in Chernobyl, where an explosion and fire in 1986 threw clouds of radioactive material over the surrounding area.”
Dr. Mark is focusing on the wrong thing - a direct breach of a reactor. That risk is apparently low. Unfortunately he provides zero comfort about the main danger - the requirement to keep the used fuel rods and reactors cool. The fuel storage ponds at Fukushima took days to heat enough to start generating hydrogen, blow up the storage buildings, and start spewing radioactivity. Lose cooling and it’s just what happens to fuel rods.
Nature has an article (https://www.nature.com/articles/d41586-022-00660-z) that acknowledges Wenman’s point (before he made it) but discusses the dangers of fuel rods. So much depends on how long they’ve been out of the reactor. Some decay products last seconds, some days, some weeks and some many years. But the longer the rods are out of the reactor, the less danger they are. There were six reactors making hot rods there so odds are good some of those ponds are a real danger if they lose cooling.
Science has an article that analyzes the risk to/of fuel rods here in the US that can give perspective on the danger now in Ukraine: https://www.science.org/content/article/spent-fuel-fire-us-soil-could-dwarf-impact-fukushima The stroke of luck they mention with Japan’s fuel rod fires at Fukushima is merely that the wind at the time of the explosions and fires in the fuel rod storage areas blew most of the fallout out to sea instead of over the east coast of Japan. Had the wind been different, Japan could still be reeling from Fukushima with the effects many times worse than they are now.
And it’s important to say things may be fine. If cooling is maintained, no problem. The risk is if Putin keeps being stupid and a danger to world, that could lead to these scenarios again for no reason, no need. Just a vindictive little man at the end of his reign, and fucking it all up so very badly.